Comparison of vibrotactile thresholds with physical examination and electrophysiological assessment.

Measurement of cutaneous vibrotactile thresholds may be useful for assessment of the functional integrity of the somatosensory system. To validate a rapid method of determining vibrotactile thresholds that uses a commercially available electromechanical device, vibrotactile thresholds were compared with standardized physical examination findings of sensory function and electrophysiological parameters in 79 patients referred to the Mount Sinai Hospital Neurophysiology Laboratory for clinical electrophysiological evaluation. A statistically significant monotonic association between graded physical examination of vibration perception and vibrotactile threshold was observed for all digits tested in the upper and lower extremities. Statistically significant associations were also observed between vibrotactile thresholds and a variety of electrophysiological measures of the median, ulnar, tibial, peroneal, and sural nerves. The strongest associations were observed between great toe vibrotactile thresholds and late response latencies measured in nerves in the lower extremities. Determination of vibrotactile thresholds may be useful in settings where quantitative measures of large fiber nerve function are desirable and electrophysiological study is not feasible.